The right answer is dark matter.
Air has particles that can interact eletromagnetically, so it is not invisible.
Dark matter, to this day, is known for it's great gravitional attraction and it's capability of not interacting with photons.
An object with gravity so strong that nothing can escape is called a black hole. These regions of spacetime have such intense gravitational force that they trap even light, which is why they appear "black" or invisible to outside observers.
Gravity does not depend on density. Gravity is the gravitational pull that is invisible and cannot be touched or changed. Density is how much matter is packed within an object, which can be changed. Gravity and density are two totally different things, and are in no way related, therefore gravity does not depend on density.
Gravity and Magnetism.
The amount of gravity acting on an object is its weight. Weight is the force exerted on an object due to gravity, and it is directly proportional to the object's mass.
Any object with mass affects gravity
No, but the centre of gravity need not be inside the object. Not unless Gravity is not a variable. But it is not possible for an object to not have a center of mass.
No, we cannot see all of the forces that affect an object because some forces, like gravity or magnetic forces, are invisible to the naked eye. However, we can observe the effects of these forces on the object's motion or behavior.
The weight of an object is the force of gravity.
weight is defined as the product of mass and gravity constant. as the value of gravity changes weight is also changed
Any object that has mass - i.e., any object - has gravity.
The force with which gravity pulls an object is called its weight. This weight is determined by the mass of the object and the acceleration due to gravity at that location.
An object's mass remains the same regardless of the influence of gravity. Mass is a measure of the amount of matter in an object and is independent of gravity. Gravity affects the weight of an object, which is the force of gravity acting on an object's mass.